Originally Posted by
garboozle
Say if a male of about 5'11 160 was tested and he smoked cannabis once a month the previous four months, and was an infrequent user the months before hand what would his chances of passing be?
Hair is a very poor medium for the detection of cannabis metabolites. Usually the use must be frequent and cumulative over a period. Axillary hair has about the same incorporation rate as scalp hair but a slower growth rate which makes the detection time longer. It is not likely that metabolites made it into any of your hair but is remotely possible.
In regard to your question of accuracy, that relates to the specific drug tested for. For cannabis metabolites it isn't accurate except in heavy users.
DuPont 2008,
Random Student Drug Tests Are They Effective for Identifying Occasional Drug Users? p. 8
Galanter & Kleber, 2011
Psychotherapy for the Treatment of Substance Abuse, American Psychiatric Publishing, Wash, DC, p. 58
Marilyn A. Huestis (2007)
Human Cannabinoid Pharmacokinetics. Chem Biodivers. 2007 August; 4(8): 1770–1804. Sec 3.5